1. Technical Field
Exemplary embodiments of the present inventive concept relate to a memory controller and a method of operating the same.
2. Discussion of Related Art
A semiconductor memory device may be a volatile semiconductor memory device or a nonvolatile semiconductor memory device. A volatile semiconductor memory device is capable of realizing a high speed read/write speed but is unable to retain its stored data when an external power supply is interrupted. A nonvolatile semiconductor memory device retains its stored data even when an external power supply is interrupted. Thus, the nonvolatile semiconductor memory device is used when contents need to be preserved regardless of whether power is supplied or not.
Erase and write operations of a programmable read only memory (PROM) and an erasable PROM (EPROM) cannot be performed easily and it may be difficult for users to renew memorized contents. Since erase and write operations of an electrically EPROM (EEPROM) can be performed electrically, an EEPROM may be applied to a system that needs continuous renewal or an auxiliary memory device. Since a flash EEPROM (hereinafter it is referred to as a ‘flash memory device’) has a high integration as compared with a conventional EEPROM, it can be applied to a high capacity auxiliary memory device. A NAND-type flash memory device has very high integration as compared with other flash EEPROMs.
However, a flash memory device may become faulty if it is programmed or erased more times than it can support.